Dispersible herbicidal compositions and methods of use

ABSTRACT

Herbicidal dispersible concentrates include an herbicide and substantially water miscible amide-based solvents. Such concentrates may be diluted in water and used in methods to control weeds.

STATEMENT OF RELATED APPLICATIONS

This application is a divisional of U.S. application Ser. No.13/950,604, filed Jul. 25, 2013, which claims priority to U.S.Provisional Application No. 61/741,819 filed Jul. 25, 2012, the contentsof which are incorporated herein by reference in their entirety.

BACKGROUND

Embodiments disclosed herein generally relate to herbicidal compositionsand methods of using the same. More particularly, embodiments disclosedherein relate to dispersible compositions that facilitate dissolution ofherbicidal active ingredients for efficient application.

Herbicides have enjoyed widespread use in commercial agriculture andhave enabled an increase in crop yields and product quality. They areroutinely used to control various weeds, for example, grasses andbroadleaved weeds such as amaranthus, foxtails and others, wheneverthese weeds pose risks to crop yield.

Topramezone is an exemplary herbicide with a favorable herbicidalactivity profile. It, like related herbicides with similar solubilityprofiles, is often formulated as a water dispersible granule (WG) or asa suspension concentrate (SC), i.e., a solid suspension. In suchformulations, the active ingredients may be milled to a particular sizeand the solid subsequently suspended in an aqueous-based carriervehicle. The WG formulation is typically made with inert compounds thathave little adjuvancy and it can be difficult to make the activeingredient bioavailable to control weeds. Particulate size of the activeingredient in these formulations, and during application, often remainstoo large such that a substantial amount of the formulation has to beapplied per acre to control weeds.

Similarly, a suspension concentrate formulation has the disadvantagethat adjuvants are hard to incorporate at a useful rate and they providelittle impetus for foliar uptake and biotranslocation, and thus asubstantial amount of the formulation has to be applied per acre tocontrol weed infestations.

SUMMARY

In some aspects, embodiments disclosed herein provide dispersibleconcentrates comprising about 0.1% to about 40% by weight of theconcentrate of a methylsulfonylphenyl ketone herbicide and about 0.6% toabout 90% by weight of the concentrate of a water-miscible amidesolvent.

In some aspects, embodiments disclosed herein provide dispersibleconcentrates comprising about 0.1% to about 40% by weight of theconcentrate of topramezone and about 0.6% to about 90% by weight of theconcentrate of N-methyl pyrrolidone.

In some aspects, embodiments disclosed herein provide formulationscomprising a dispersible concentrate and water, the dispersibleconcentrate comprising about 0.1% to about 40% by weight of theconcentrate of a methylsulfonylphenyl ketone herbicide and about 0.6% toabout 90% by weight of the concentrate of N-methyl pyrrolidone, whereina ratio of dispersible concentrate to water is in a range from about1:50 to 1:25,000 by volume, and wherein the formulation is in the formof a colloidal suspension.

In some aspects, embodiments disclosed herein provide methods oftreating weeds comprising applying to the weeds an herbicidallyeffective amount of a formulation comprising a dispersible concentrateand water, the dispersible concentrate comprising about 0.1% to about40% by weight of the concentrate of a methylsulfonylphenyl ketoneherbicide and about 0.6% to about 90% by weight of the concentrate ofN-methyl pyrrolidone, wherein in a ratio of dispersible concentrate towater is in a range from about 1:50 to 1:25,000 by volume, and whereinthe formulation is in the form of a colloidal suspension.

DETAILED DESCRIPTION

Embodiments disclosed herein provide dispersible concentrates comprisingabout 0.1% to about 40% by weight of the concentrate of amethylsulfonylphenyl ketone herbicides and about 0.6% to about 90% byweight of the concentrate of a water-miscible amide solvent. Inparticular embodiments, the water miscible solvent is N-methylpyrrolidone. N-methyl pyrrolidone (NMP) is a cyclic amide-based polaraprotic solvent that is substantially miscible with water in most anyratio. When an NMP solution containing an organic compound goes intowater, NMP may immediately dissolve into the water phase and the organiccompound may begin to precipitate or separate into a second liquidphase. If the organic compound of interest is an active herbicidal agentthat separates rapidly, either the particle size may be difficult tocontrol or the phase separation may render water-based application ofthe herbicide ineffective due to lack of solubility in water.

In the case of topramezone, and other methylphenylsulfonyl ketoneherbicides disclosed herein, it has been discovered that their highlypH-dependent water solubility profiles (typically low below the pK_(a)and fairly high above the pK_(a)) is compatible with, and even desirablefor preparing amide-based concentrates, such as NMP concentrates. Suchconcentrates can be readily diluted with water to provide a colloidalsuspension ideal for the treatment of weeds. Without being bound bytheory, amide-based solvents may serve a dual role in successfullypreparing the colloidal formulations disclosed herein: (1) amide-basedsolvents generally quickly solubilize methylphenylsulfonyl ketoneherbicides in a shelf-stable concentrate and (2) amide-based solventsmay provide a sufficient increase in operational pH after water dilutionto prevent crystallization. By contrast, current suspension concentratesof these herbicides are manufactured at a pH below their pK_(a) to avoidcrystal growth during storage. When they are diluted the pH is low andthe material is poorly solubilized and sprayed predominantly as a solidrather than a solution. As disclosed herein, the colloidal formulationsprepared from amide-based dispersible concentrates demonstrate improvedefficacy in the treatment of weeds in field trials. As used herein,“colloidal suspension” or “colloidal formulation” is distinguished fromthe coarse granule suspensions employed in the art in that the particlesize is generally smaller in the colloidal system. In embodiments, thecoarse granules of commercially available tompramezone, for example, maybe greater than about 1 micron, or greater than about 5 microns, orgreater than about 10 microns. By contrast, the colloidal formulationsdisclosed herein may be less than about 1 micron in size. This smallerparticle size confers greater water solubility to the active ingredient,which ultimately provides greater delivery efficiency in the field.

One skilled in the art will appreciate that the principles that governthe successful use of NMP, as demonstrated in the Examples below, as thesolvent vehicle for the dispersible concentrate may be obtained withsimilar polar aprotic solvents. Thus, other amide-based solvents thatare highly miscible with water may be employed, including, withoutlimitation, N,N-dimethylformamide (DMF), N,N-dimethylacetamide,formamide, N-methylformamide, and the like. Any amide-based solvent maybe useful due to their ability to provide a slight increase in pH inwater. In embodiments, other polar protic solvents may also be useful,albeit, with a lesser influence on pH. Thus, in embodiments, solventssuch as dimethyl sulfoxide (DMSO), sulfolane, tetrahydrofuran (THF), andsimilar polar aprotic solvents may be useful. In embodiments, polaraprotic solvents may be selected for use in generating concentratesbased on environmental and/or biocompatibility. In this regards,N-methyl pyrrolidone is particularly suitable.

Other solvents, co-solvents and/or additives (in any amount) that may bepresent in the concentrates or formulations disclosed herein include,without limitation, 1,3-Propanediol (CAS Reg. No. 504-63-2),2-Ethyl-1-hexanol (CAS Reg. No. 104-76-7), 2-Ethylhexanol,2-methyl-1,3-propanediol (CAS Reg. No. 2163-42-0),2-Methyl-2,4-pentanediol, Acetic anhydride, Acetone (Cas Reg. No.67-64-1), Ammonium hydroxide, Amyl acetate, C10-11 rich aromatichydrocarbons (CAS Reg. No. 64742-94-5), C11-12 rich aromatichydrocarbons (CAS Reg. No. 64742-94-5), C9 rich aromatic hydrocarbons(CAS Reg. No. 64742-95-6), Chlorobenzene, Choline chloride (CAS Reg. No.67-48-1), Cod liver oil, Cyclohexane, Cyclohexanone, Cyclohexanone,Decanamide, N,N-dimethyl (CAS Reg. No. 14433-76-2), Diethylene Glycol(CAS No. 111-46-6), Diethylphthalate, Diisopropyl adipate (CAS Reg. No.6938-94-9), Dipropylene glycol, d-Limonene (CAS Reg. No. 5989-27-5),Ethyl acetate, Ethyl alcohol, Ethyl esters of fatty acids derived fromedible fats and oils, Glycerol mono-, di-, and triacetate, Isobornylacetate, Isobutane (CAS Reg. No. 75-28-5), Isobutyl alcohol, Isopropylmyristate (CAS Reg. No. 110-27-0), Isopropyl myristate, CAS Reg. No.110-27-0, Kerosene, U.S.P. reagent, Lactic acid, Lactic acid,2-ethylhexyl ester (CAS Reg. No. 6283-86-9), Lactic acid, 2-ethylhexylester, (2S)-(CAS Reg. No. 186817-80-1), Lactic acid, n-propyl ester,(S); (CAS Reg. No. 53651-69-7), Mesityl oxide, Methyl5-(dimethylamino)-2-methyl-5-oxopentanoate (1174627-68-9), Methylalcohol, Methyl esters of fatty acids derived from edible fats and oils,Methyl isobutyl ketone, Methyl isobutyl ketone, Methyl isobutyl ketone,Methyln-amyl ketone (CAS Reg. No. 110-43-0), Mineral oil, U.S.P., orconforming to 21 CFR 172.878 or 178.3620(a), (b), Morpholine 4-C6-12AcylDerivatives (CAS Reg. No. 887947-29-7), n-Butanol (CAS Reg. No.71-36-3), n-Decyl alcohol (CAS Reg. No. 112-30-1), n-Hexyl alcohol (CASReg. No. 111-27-3), N-Methylpyrrolidone (CAS Reg. No. 872-504), n-Octylalcohol (CAS Reg. No. 111-87-5), n-Propanol, Oleyl alcohol (CAS Reg. No.143-28-2, Oxo-decyl acetate (CAS reg. No. 108419-33-6), Oxo-heptylacetate (CAS Reg. No. 90438-79-2), Oxo-hexyl acetate (CAS Reg. No.88230-35-7), Oxo-nonyl acetate (CAS Reg. No. 108419-34-7), Oxo-octylacetate (CAS Reg. No. 108419-32-5), Oxo-tridecyl acetate (CAS Reg. No.108419-35-8), Petroleum hydrocarbons, light odorless conforming to 21CFR 172.884, Petroleum hydrocarbons, light, odorless, conforming to 21CFR 172.884 or 178.3650, Petroleum hydrocarbons, syntheticisoparaffinic, conforming to 21 CFR 172.882, Petroleum hydrocarbons,synthetic isoparaffinic, conforming to 21 CFR 172.882 or 178.3530,Phenol, Propylene glycol, Propylene glycol monomethyl ether, Soybeanoil-derived fatty acids, Tetrahydrofurfuryl alcohol (THFA) (CAS Reg. No97-99-4), Toluenesulfonic acid and its ammonium, calcium, magnesium,potassium, sodium, and zinc salts, Triacetin (glyceryl triacetate),Xylene.

In particular embodiments, sovlents that may be useful in conjunctionwith concentrates and formulations disclosed herein include, withoutlimitation, amyl acetate, ethyl acetate, methyl or ethyl esters of fattyacids derived from edible fats and oils, glycerol mono-, di-, andtriacetate, lactic acid, 2-ethylhexyl ester (CAS Reg. No. 6283-86-9),lactic acid, 2-ethylhexyl ester, (2S)-(CAS Reg. No. 186817-80-1), lacticacid, n-propyl ester, (S) (CAS Reg. No. 53651-69-7), methyl isobutylketone, decanamide, N,N-dimethyl (CAS Reg. No. 14433-76-2), andN-Methylpyrrolidone, morpholine 4-C6-12Acyl Derivatives (CAS Reg. No.887947-29-7).

In embodiments, formulations prepared from polar aprotic solventconcentrates may be selected for an operation pH in a range from about 5to about 10, or in a range from about 6.5 to about 7.5. In general,solvents may be selected for use with methylsulfonyl phenyl ketoneherbicides with a water solubility of greater than about 5% and thatyield formulations upon dilution with a pH of greater than or equal toabout 5. One skilled in the art will appreciate that any activeherbicidal ingredient-solvent pairing for generating a dispersibleconcentrate may be provided based on solubility, and in consideration ofany pH dependency on solubility. In particular, amide based solvents mayprovide good operational capacity for any active ingredient that has afavorable solubility profile above about pH 5.

In embodiments, the dispersible concentrates may further comprise anorganic co-solvent selected from the group consisting of ethyl lactate,ethyl hexyl lactate, fatty acid dimethylamide, N,N-dimethyloctanamide,and N,N-dimethyldecanamide. In embodiments, such a co-solvent may serveas a wetting agent.

In embodiments, the methylsulfonylphenyl ketone herbicide comprises oneselected from the group consisting of topramezone, isoxaflutole,mesotrione, sulcotrione, tembotrione, and combinations thereof. Thesecompounds share a common structural profile and may exhibit similarsolubility-pH dependencies. In embodiments, the methylsulfonylphenylketone herbicide is topramezone:

Methylsulfonylphenyl ketone herbicides share a structural feature of acentral phenyl ring bearing a ketone group and a methanesulfonyl groupas in structure I:

In structure I, X may be C₁ to C₆ straight chain or branched alkyl,cycloalkyl, halogen, aryl, heteroaryl, trifluoromethyl, nitro, oxo,carboxy, or carboxyalkyl, any of which may be optionally substituted.Optional substitution includes any degree of substitution, such asmonosubstitution up to fully-substituted. Optional substituents include,without limitation, fluoro, bromo, chloro, C₁ to C₆ straight chain orbranched alkyl. In particular embodiments, X is any electron withdrawinggroup as understood by those skilled in the art. That is, any groupgenerally understood to reduce electron density in the phenyl ring towhich substituent X is attached. In structure I, R may be any cyclicgroup, including aryl, heteroaryl, biaryl, cycloalkyl, heterocycloalkyland the like, any of which may be optionally substituted. In particularembodiments, R is a cyclohexanedione moiety. In embodiments, R may bebased on acyclic aliphatic structures as well.

In embodiments, there are provided compounds of structure II:

-   wherein R₁ is selected from:

-   R₂ is selected from methyl, nitro, chloro, and methanesulfonyl;

-   R₃ is selected from hydrogen, —CH₂—O—CH₂—CF₃, and-   R₄ is selected from methanesulfonyl, trifluoromethyl, and chloro;    and-   R₅ and R₆ are hydrogen.

In embodiments, structure II is topramezone:

In embodiments, structure II is isoxflutole:

In embodiments, structure II is mesotrione:

In embodiments, structure II is sulcotrione:

In embodiments, structure II is tembotrione:

In embodiments, the methylsulfonylphenyl ketone herbicide is topramezoneand its concentration may be in a range from about 5% to about 25% byweight of the concentrate, or from about 10% to about 20% by weight ofthe concentrate.

In embodiments, the dispersible concentrate may further comprise asurfactant. In some such embodiments, the surfactant comprises oneselected from the group consisting of butyl polyalkylene oxide blockcopolymers, polyalkylene oxide block copolymers, tristyrylphenolethoxylates, alkylphenol ethoxylates, castor oil ethoxylates, acetylenicpolydiols, organosilicones and mixtures thereof. In embodiments, thesurfactant comprises organosilicones. In embodiments, theorganosilicones comprise a polyalkyleneoxide modifiedheptamethyltrisiloxane. In embodiments, the surfactant further comprisesan alkyloxypolyethyleneglycol methyl ether. In some such embodiments,the ratio of polyalkyleneoxide modified heptamethyltrisiloxane andallyloxypolyethyleneglycol methyl ether is in a range of from 80:20 to90:10 percent weight based on the total weight of the concentrate. Inembodiments, the surfactant is present in an amount of from about 0.1%to about 15% by weight of the dispersible concentrate.

In embodiments, there are provided dispersible concentrates comprisingabout 0.1% to about 40% by weight of the concentrate of topramezone andabout 0.6% to about 90% by weight of the concentrate of N-methylpyrrolidone. In particular embodiments, the dispersible concentratecomprises from about 10% to about 20% topramezone. In some embodiments,such concentrates may further comprises an organic co-solvent selectedfrom the group consisting of ethyl lactate, ethyl hexyl lactate, fattyacid dimethylamide, N,N-dimethyloctanamide, and N,N-dimethyldecanamide.In embodiments, such dispersible concentrates may further comprise asurfactant.

In some embodiments, there are provided formulations comprising adispersible concentrate and water, the dispersible concentratecomprising about 0.1% to about 40% by weight of the concentrate of amethylsulfonylphenyl ketone herbicide, and about 0.6% to about 90% byweight of the concentrate of N-methyl pyrrolidone, wherein in a ratio ofdispersible concentrate to water is in a range from about 1:50 to1:25,000 by volume, and wherein the formulation is in the form of acolloidal suspension.

In embodiments, the formulation may further comprise an additiveselected from the group consisting of a surfactant, urea-ammoniumnitrate (UAN), and combinations thereof. In embodiments, the formulationmay comprise a methylsulfonylphenyl ketone herbicide comprisingtompramezone. In some embodiments, topramezone is present in a rangefrom about 10% to about 20% by weight of the concentrate. Inembodiments, the dispersible concentrate further comprises an organicco-solvent selected from the group consisting of ethyl lactate, ethylhexyl lactate, fatty acid dimethylamide, N,N-dimethyloctanamide, andN,N-dimethyldecanamide.

In embodiments, there are provided methods of treating weeds comprisingapplying to the weeds an herbicidally effective amount of a formulationcomprising a dispersible concentrate and water, the dispersibleconcentrate comprising about 0.1% to about 40% by weight of theconcentrate of a methylsulfonylphenyl ketone herbicide, and about 0.6%to about 90% by weight of the concentrate of N-methyl pyrrolidone,wherein in a ratio of dispersible concentrate to water is in a rangefrom about 1:50 to 1:25,000 by volume, and wherein the formulation is inthe form of a colloidal suspension.

In embodiments, methods disclosed herein may be used against weeds thatare monocots or dicots. In embodiments, the weeds are resistant toglyphosate. In embodiments, methods disclosed herein may employ amethylsulfonylphenyl ketone herbicide comprising topramezone in aconcentration in a range from about 10% by weight of the concentrate toabout 20% by weight of the concentrate. In embodiments, suchformulations may further comprise an additive selected from the groupconsisting of a surfactant, urea-ammonium nitrate (UAN), andcombinations thereof.

Embodiments disclosed herein relate to a dispersible concentrate (DC)composition comprising from about 0.1% to about 40% by weight oftopramezone and from about 0.6% to about 90% by weight of a solvent,wherein the solvent has water solubility of between about 0.1% and about100%, and wherein the weight percentages are based on the total weightof the composition.

Embodiments disclosed herein provide a dispersible concentrate whichforms a liquid-suspension of topramezone particles upon dilution withwater. The particles are of sufficiently small size to facilitate rapiddissolution and improve application in the field to control weeds whilereducing the amount of topramezone employed.

In one aspect, embodiments disclosed herein provide methods of preparingreadily-solubilized dispersions of topramezone comprising diluting thedispersible concentrate compositions disclosed herein in water at aratio from about 1:50 to about 1:25000 (composition: water) by volume,or from about 1:200 to about 1:5000 by volume.

In one aspect, embodiments disclosed herein provide a method forincreasing the herbicidal efficacy of a liquid-dispersion of topramezonefor a crop, comprising preparing a formulation comprising an effectiveamount of topramezone.

In one aspect, embodiments disclosed herein also provide a formulationcomprising a. from about 0.00004% to about 0.8% by weight oftopramezone; b. from about 0.0008% to about 1.5% by weight of a solvent,wherein the solvent has water solubility of between about 0.1% and about100%; c. from about 95% to about 99.999% by weight of water, and; d.optionally a surfactant from about 0.00001% to about 0.35%, wherein theweight percentages are based on the total weight of the composition.

In another aspect, embodiments disclosed herein provide methods ofcontrolling weeds, such as monocot and dicot weeds. In certainembodiments, the method includes applying a formulation prepared fromthe DC composition to a crop plant in need of weed control or at risk ofundesirable weeds.

Embodiments disclosed herein provide a dispersible concentrate (DC)composition comprising from about 0.1% to about 40%, by weight oftopramezone[3-(4,5-dihydro-1,2-oxazol-3-yl)-4-mesyl-o-tolyl](5-hydroxy-1-methyl-1H-pyrazole-4-yl)methanoneand from about 0.6% to about 90% by weight of a solvent, wherein thesolvent has water solubility of between about 0.1% and about 100%, andwherein the weight percentages are based on the total weight of thecomposition.

In certain embodiments, the dispersible concentration includestopramezone in the amount of from about 0.1% to about 40%, from about10% to about 20% or from about 14% to about 18% by weight based on thetotal weight of the composition.

In certain embodiments, the dispersible concentration includes a solventin the amount of from about 0.6% to about 90%, from about 30% to about90%, from about 60% to about 90% or from about 75% to about 85% byweight based on the total weight of the composition.

Solvents that are suitable for use in the DC compositions include, butnot limited to, N-methyl pyrrolidone, ethyl lactate, ethyl hexyllactate, fatty acid dimethylamide, N,N-dimethyloctanamide,N,N-dimethyldecanamide, and a blend or mixtures thereof. In certainembodiments, the solvent does not include water, thus, providing anon-aqueous DC composition. In such embodiments, it will be understoodthat a certain amount of water may be present due to normal exposure tothe environment and thus, the compositions should not be consideredlimited to be strictly anhydrous, although such anhydrous preparationscan be made and are within the scope of the compositions disclosedherein. In certain embodiments, the solvent does not include aliphaticalcohol ethoxylates.

As used herein, the term “surfactant” encompasses a blend ofsurfactants. The DC compositions may exhibit surprisingly gooddispersion properties, good herbicidal efficacy, and reduced herbicideuse compared to other commonly used formulation types.

In certain embodiments, the solvent in the composition comprisesN-methyl pyrrolidone, ethyl lactate, ethyl hexyl lactate, fatty aciddimethylamide, N,N-dimethyloctanamide, N,N-dimethyldecanamide, ormixtures thereof (i.e., blends of two or more solvents).

The water solubility of the solvent in the DC composition may be in arange from about 0.1% to infinitely miscible based on the total weightof the concentrate. When two or more solvents are present in the DCcomposition, the water solubility may be calculated based on thecombined effect of the solvent mixtures.

The DC compositions may further comprise a surfactant. The surfactantmay include a butyl polyalkylene oxide block copolymers, polyalkyleneoxide block copolymers, tristyrylphenol ethoxylates, alkylphenolethoxylates, castor oil ethoxylates, acetylenic polydiols,organosilicones, or mixtures thereof. In certain embodiments, thesurfactant includes organosilicones. In further embodiments, thesurfactant includes a polyalkyleneoxide modified heptamethyltrisiloxane.In yet further embodiments, the surfactant comprises anallyloxypolyethyleneglycol methyl ether. In certain embodiments, theratio of polyalkyleneoxide modified heptamethyltrisiloxane toallyloxypolyethyleneglycol methyl ether may be in a range of from 80:20to 90:10 percent weight based on the total weight of the compostion. Ina specific embodiment, the surfactant includes Silwet L-77®.

The amount of surfactant in the DC compositions may be from about 0.1%to about 15% by weight of the composition; or from about 5% to about 15%by weight based on the total weight of the composition.

Embodiments disclosed herein also provide a method of forming aliquid-suspension of topramezone by dilution of a DC composition in aratio from about 1:50 to about 1:25000 (DC: water), or in a ratio fromabout 1:200 to about 1:5000 by volume with water.

Embodiments disclosed herein provide formulations prepared from the DCcompositions disclosed herein.

The formulation disclosed herein may include: a. from about 0.00004% toabout 0.8% by weight of topramezone; b. from about 0.0008% to about 1.5%by weight of a solvent, wherein the solvent has water solubility of fromabout 0.1% and about 100%; c. from about 95% to about 99.999% by weightof water, and; d. optionally a surfactant from about 0.00001% to about0.35%, wherein the weight percentages are based on the total weight ofthe formulation.

In certain embodiments, the formulation includes from about 0.0008% toabout 4.0% by weight of a solvent based on the total weight of theformulation.

In certain embodiments, the formulation includes from about 96.9% toabout 99.99% by weight of water based on the total weight of theformulation.

Formulations disclosed herein can be produced by mixing or suspendingtopramezone, optionally an adjuvant, optionally a stabilizer, and adiluent or a solvent.

It is well within a skill of the art to prepare such formulations usingwell-known techniques, such as dilutions. The dilutions may be made inwater. The dilutions may be made by adding water to the DC compositionat a ratio from about 1:50 to about 1:25000 (DC: water) or at a ratiofrom about 1:200 to about 1:5000) by volume. In general, ratios ofdilution varies depending upon the concentration of the activeingredient (e.g., topramezone) in the DC composition in which a plant isbeing treated, the intensity of the weed infestation, weatherconditions, the predominant infesting weed species, and other factors,and may be readily determined by established biological tests known tothose skilled in the art.

Embodiments relate to methods of treating weeds comprising applying aherbicidally effective amount of the formulations disclosed herein. Aperson skilled in the art would readily know how to “treat” weeds, asthese techniques are well known in the art and are applicable to thecompositions disclosed herein. Therefore, embodiments disclosed hereinprovide methods for controlling weeds. In one embodiment, a methodincludes applying (contacting) a formulation comprising a. from about0.00004% to about 0.8% by weight of3-(4,5-dihydro-1,2-oxazol-3-yl)-4-mesyl-o-tolyl](5-hydroxy-1-methyl-1H-pyrazole-4-yl;b. from about 0.0008% to about 1.5% by weight of a solvent, wherein thesolvent has water solubility of between about 0.1% and about 100%; c.from about 95% to about 99.999% by weight of water, and; d. optionally asurfactant from about 0.00001% to about 0.35%, wherein the weightpercentages are based on the total weight of the composition, to a weed,a crop or a plant habitat or area. Such methods are applicable to aplant including, but not limited to, one or more weeds described herein.

The phrase “herbicidally effective amount” of the formulation means asufficient amount of the formulation to provide the desired effect. Ingeneral, the formulation is employed in amounts that do not causephytotoxic damage to any part of the crop but still effectively controlsthe weeds threatening the crop. The amount of the formulation may varydepending on specific crops and other factors. It is well within anordinary skill in the art to determine the necessary amount of theformulation. A crop for the purpose of embodiments disclosed hereinrefers but is not limited to a useful agricultural commodity such ascornfield corn, seed corn, or sweet corn. Crops can be transgenic ornon-transgenic.

The formulations disclosed herein may be used against weeds includingmonocot and dicot weeds. Non-limiting examples of weeds include,Amaranthus, Burcucumber, Carpetweed, Chickweed, Cocklebur, Dandelion,Horseweed, Kochia, Lambsquarters, Nightshade, Pigweed, Ragweed,Smartweed, Thistle, Velvetleaf, Waterhemp, Foxtails, Barnyardgrass andothers. In certain embodiments, the weeds are glyphosate resistantweeds, amino lactate synthase resistant weeds, triazine resistant weeds,HPPD (enzyme 4-hydroxyphenyl pyruvate dioxygenase) resistant wees andthe like.

In another embodiment, the formulation can be applied to soil, pre andpost planting and to growing crops as a spray.

As used herein, the singular forms “a”, “and,” and “the” include pluralreferents unless the context clearly indicates otherwise

As used herein, all numerical values relating to amounts, weights, andthe like, are defined as “about” or “approximately” each particularvalue, namely, plus or minus 10%. For example, the phrase “at least 5%by weight” is to be understood as “at least 4.5% to 5.5% by weight.”Therefore, amounts within 10% of the claimed value are encompassed bythe scope of the claims.

For a clearer understanding of the embodiments disclosed herein,specific examples are set forth below. These examples are merelyillustrations and are not to be understood as limiting the scope andunderlying principles of the various embodiments in any way. Indeed,various modifications of the various embodiments in addition to thoseshown and described herein will become apparent to those skilled in theart from the following examples and foregoing description. Suchmodifications are also intended to fall within the scope of the appendedclaims.

EXAMPLES

Materials: Agnique KE 3658 is a fatty acid dimethylamide solventavailable from Cognis USA, Cincinnati, Ohio 45232. Agsolex1 isN-methyl-2-pyrrolidone, a solvent supplied by Ashland Corporation.Purasolv EL is Ethyl Lactate, a solvent supplied by Purac America, Inc.Purasolv EHL is Ethyl Hexyl Lactate, a solvent supplied by PuracAmerica, Inc. Halcomid M8-10 is a fatty acid dimethylamide solventavailable from Stepan Company, Northfield, Ill. 60093. Silwet L-77® is amixture of polyalkeleneoxide modified heptamethyltrisiloxane andallyloxypolyethyleneglycol methyl ester and is a surfactant supplied byGE silicones. Surfynol 465 is an acetylenic polydiol surfactant suppliedby Air Products. Emulpon CO-360 is a castor oil ethoxylate non-ionicsurfactant available from Akzo Nobel Surfactants, Chicago, Ill. 60607.Makon TSP 16 is a tristyrylphenol ethoxylate non-ionic surfactant fromavailable from the Stepan Co., Northfield, Ill. 60093. Stepfac TSP-PE isa tristyrylphenol ethoxylate phosphate ester anionic surfactant and isavailable from the Stepan Co., Northfield, Ill. 60093. Soprophor BSU isa tristyrylphenol ethoxylate non-ionic surfactant and is available fromRhodia, Cranbury, N.J. 08512. Soprophor 3D33 is a tristyrylphenolethoxylate phosphate ester anionic surfactant such as2,4,6-tris(1-phenylethyl)polyoxyethylene phosphate and is available fromRhodia, Cranbury, N.J. 08512. Toximul 8320 is a butyl polyalkylene oxideblock copolymer non-ionic surfactant available from the Stepan Co.,Northfield, Ill. 60093. As used herein, “topramezone technical” contains97-100% by weight topramezone.

Example 1

A formulation was prepared by conventional blending techniquesconsisting of topramezone technical at about 15% by weight, an amidesolvent Agnique KE 3658 at about 10% by weight, N-methyl-2-pyrrolidonesolvent at about 75%, wherein the weight percentages are based on thetotal weight of the composition. The Topramezone technical was firstdissolved into N-methyl-2-pyrrolidone. Then, Agnique KE 3658 was added.The mixture was then blended until a clear homogeneous solution wasobtained. The formulation had good dispersion properties forming areadily-solubilized suspension of topramezone particles upon dilutionwith water.

Example 2

A formulation was prepared by conventional blending techniquesconsisting of topramezone technical at about 12% by weight, a surfactantSilwet L-77® at about 16% by weight, an amide solvent, like HalcomidM-8-10, at about 10% by weight, a solvent N-methyl-2-pyrrolidone atabout 62% by weight, wherein the weight percentages are based on thetotal weight of the composition. The Topramezone technical was firstdissolved into a blend of Halcomid M-8-10 and N-methyl-2-pyrrolidone.Then, Silwet L-77® was added. The mixture was then blended until a clearhomogeneous solution was obtained. The formulation had good dispersionproperties forming a readily-solubilized suspension of topramezoneparticles upon dilution with water.

Example 3

A formulation was prepared by conventional blending techniquesconsisting of topramezone technical at about 3% by weight, a surfactantToximul 8320 at about 12% by weight, a solvent Purasolv EL at about 85%by weight, wherein the weight percentages are based on the total weightof the composition. The Topramezone technical was first dissolved intoPurasolv EL. Then, Toximul 8320 was added. The mixture was then blendeduntil a clear homogeneous solution was obtained. The formulation hadgood dispersion properties forming a readily-solubilized suspension oftopramezone particles upon dilution with water.

Example 4

A formulation was prepared by conventional blending techniquesconsisting of topramezone technical at about 17% by weight, a solventN-methyl-2-pyrrolidone at about 83% by weight, wherein the weightpercentages are based on the total weight of the composition. Thetopramezone technical was dissolved into N-methyl-2-pyrrolidone. Themixture was then blended until a clear homogeneous solution wasobtained. The formulation had good dispersion properties forming areadily-solubilized suspension of topramezone particles upon dilutionwith water and is expected to have good biological efficacy.

Example 5

A formulation was prepared by conventional blending techniquesconsisting of topramezone technical at about 2% by weight, a surfactantSurfynol 465 at about 15% by weight, a solvent ethyl hexyl lactate atabout 83% by weight, wherein the weight percentages are based on thetotal weight of the composition. The Topramezone technical was firstdissolved into the ethyl hexyl lactate. Then, Surfynol 465 added. Themixture was then blended until a clear homogeneous solution wasobtained. The formulation had good dispersion properties forming areadily-solubilized suspension of topramezone particles upon dilutionwith water.

Example 6

A formulation was prepared by conventional blending techniquesconsisting of topramezone technical at about 10% by weight, a surfactantEmulpon C0-360 at about 14% by weight, and a solventN-methyl-2-pyrrolidone at about 76% by weight, wherein the weightpercentages are based on the total weight of the composition. Thetopramezone technical was first dissolved into N-methyl-2-pyrrolidone.Then, EmulponCO-360 was added. The mixture was then blended until aclear homogeneous solution was obtained. The formulation had gooddispersion properties forming a readily-solubilized suspension oftopramezone particles upon dilution with water.

Example 7

This Example shows stability tests performed on exemplary dispersibleconcentrates.

Dispersible concentrates were prepared in triplicate and the tested forstability which is summarized in Table 1 below. Concentrates A, B, and Cwere prepared by dissolution of about 15% by weight of the concentrateof topramezone technical in N-methyl pyrrolidone.

TABLE 1 Concentrate A Concentrate B Concentrate C 2 weeks 2 weeks 2weeks 2 weeks 2 weeks 2 weeks Test Initial 20° C. 54° C. Initial 20° C.54° C. Initial 20° C. 54° C. Assay (% w/w) 15.0 15.0 15.1 14.8 14.7 14.914.8 14.8 15.0 pH (1% dilution 6.5 6.4 6.2 6.4 6.4 6.1 6.5 6.3 6.2 in DIwater) Suspensibility in 342 ppm 100 100 100 100 100 100 100 100 100water

The concentrates exhibited excellent stability after two weeks at 20° C.and at 54° C., the latter temperature being considered by the EPA andthe EU to be equivalent to one year stability. By contrast, thesuspension concentrates (coarse dispersion) employed in the art areinherently thermodynamically unstable as they tend to settle, form asupernatant layer with time and are prone to viscosity changes as wellas particle size growth. The dispersible concentrates disclosed hereinare not susceptible in this manner.

Example 8

This Example shows test DC Formulations A, B, and C diluted with waterand applied against various weeds with effectiveness compared against astandard suspension (coarse dispersion) formulation. The preparation ofDC Formulation A, B, and C (Table 2) was accomplished by dissolvingtechnical grade topramezone in N-methyl pyrrolidone and then adding thewetting/penetrating agent. The final solutions were translucent goldenin color.

TABLE 2 Ingredients Formula A Formula B Formula C N-methyl pyrrolidone73.2 73.2 73.2 Topramezone technical 15 15 15 Silwet L-77 11.8 0 5.9Ethyl lactate 0 11.8 5.9 Total 100 100 100

These experimental formulations were compared to the current standardcommercial formulation of topramezone designated as a 2.8 pound activeingredient per gallon Suspension Concentrate (2.8 SC). Formulationstested in the field were constructed as 1.29 pound per gallonDispersible Concentrate (1.29 DC). All field trial testing compared thestandard formulation with the experimental formulations at the same rateof active ingredient per acre.

In all locations, trials were conducted throughout the corn growingregion and constructed in typical small-plot fashion with each treatmentreplicated 3 or 4 times. Individual plots ranged from 6 to 12 feet wideand approximately 20 to 30 feet in length. All plots included 2 to 4rows of corn. Applications were made with a CO₂ hand-held sprayer tosimulate commercial applications. Application water volumes ranged fromapproximately 10 to 20 gallons per acre. All applications were madepost-emergence to the crop and weeds. Weed height at applicationgenerally ranged from 2 to 8 inches at the time of application. Variousnative weeds were tested at each location and the broad spectrum ofweeds included are representative of the weed flora throughout theglobal cultivated corn growing region. Evaluation of weed controlactivity was made visually and recorded as an estimated percent controlbased on the untreated control plots in each trial. A summary of testweeds are shown in Table 3 below.

TABLE 3 Scientific Name Common Name Abutilon theophrasti VelvetleafAmaranthus palmerii Palmer amaranth Amaranthus sp. Pigweed speciesAmbrosia artemisiifolia Common ragweed Brachiaria platyphylla Broadleafsignalgrass Chenopodium album Lambsquarters Hibiscus trionium Venicemallow Ipomoea sp. Momingglories Portulaca oleracea Purslane Setariafaberii Giant foxtail Setaria glauca Yellow foxtail

Several trials on different weed species were performed at standardapplication rates of herbicide. Results are summarized in Table 4 below.

TABLE 4 Formulation Weed Species, Location, Percent Control pounds RateAmaranthus Chenopodium Amaranthus Setaria Amaranthus Amaranthus activepounds active sp. album sp. glauca retroflexus palmerii ingredient/Formulation ingredient/ Springflied, Springfield, Springfield, Phelps,Ft. Collins, Stoneville, Treatment gal Type acre NE NE NE NY CO MSTopramezone 2.8  SC 0.016 71  99 64 57  65  93 Commercial Topramezone1.29 DC 0.016 87 100 88 80  98 100 Experimental ‘A’ Topramezone 1.29 DC0.016 90  99 89 70  93 100 Experimental ‘B’ Topramezone 1.29 DC 0.016 86100 93 76 100  98 Experimental ‘C’

Table 4 shows results from four locations on five different weedspecies. The standard commercial product, listed as “TopramezoneCommercial” provided 71 to 99 percent control across weed species andlocations vs. 70 to 100 percent control for the experimentalformulations. All products were used at the same rate per acre of 0.016pounds of active ingredient. In almost every case, the experimentalformulations provided better control than the Topramezone Commercialstandard. Typically, depending on cropping system, weed type anddensity, less than 75 percent control in unacceptable in crop productionand will not allow achievement of maximum crop yields. Control of 75-85percent is considered good and 86-100% is considered excellent.

Trials were also run at marginal application rates to expose differencesin treatments. The results are shown in Table 5 below.

TABLE 5 Formulation Rate per acre Weed Species, Location, PercentControl concentration (pounds Abutilon Chenopodium (pounds activeFormulation active theophrasti Amaranthus sp. album Setaria faberiiTreatment ingredient/gallon) Type ingredient) Springfield, NETopramezone 2.8  SC 0.011 10 10 10 10 Commercial Topramezone 1.29 DC0.011 40 67 50 30 Experimental ‘A’ Topramezone 1.29 DC 0.011 37 60 40 20Experimental ‘C’

Table 5 shows results of trials conducted on four weeds with thecommercial formulation and experimental formulations of topramezoneapplied at the low end of the labeled rate (0.011 pounds of activeingredient per acre, which can be used for certain weeds or in certainmixtures of herbicides). At this commercial rate the standardformulation provided only 10% control of the four weeds tested while theexperimental formulations provided from 2 to 6.7 times greater activity(20 to 67 percent control). Certain weeds, such as Chenopodium, Abutilonand others are often very difficult to control.

Further trials were run at normal application rates of herbicide withoutadded surfactant. The results are shown in Table 6 below.

TABLE 6 Formulation Rate per acre Weed Species, Location, PercentControl concentration (pounds Abutilon Chenopodium (pounds activeFormulation active theophrasti Amaranthus sp. album Setaria faberiiTreatment ingredient/gallon) Type ingredient) Springfield, NETopramezone 2.8  SC 0.016 23 38 33 20 Commercial Topramezone 1.29 DC0.016 63 63 50 27 Experimental ‘A’ Topramezone 1.29 DC 0.016 47 53 43 23Experimental ‘C’

Table 6 shows the same weeds at a higher use rate of all formulationsand again the experimental formulations provided greater activity in allcases.

Further trials were run at normal application rates of herbicide withnormally added surfactants. The results are shown in Table 7 below.

TABLE 7 Formulation Rate per acre Weed Species, Location, PercentControl concentration (pounds Abutilon Chenopodium (pounds activeFormulation active theophrasti Amaranthus sp. album Setaria faberiiTreatment ingredient/gallon) Type ingredient) Springfield, NETopramezone 2.8  SC 0.016 + surfactant* 83 80  92 53 CommercialTopramezone 1.29 DC 0.016 + surfactant* 88 90  98 92 Experimental ‘A’Topramezone 1.29 DC 0.016 + surfactant* 85 90 100 83 Experimental ‘C’*surfactant = 1% methylated sunflower oil + 2.5% urea ammonium nitrate(28%)

Table 7 shows the same formulations and application rates as Table 5,but with additional surfactants added to the spray mixture. Adjuvants,spreaders, stickers, and the like are standard commercial practice andare often added to enhance activity in specific situations. In theaddition of extra surfactants such as methylated sunflower oil (MSO)along with urea ammonium nitrate (UAN), all treatments were improved,but the experimental formulations, in each case were improved to a anoverall better level of performance and sometimes significantly better(e.g., Setaria, Amaranthus) performance than the standard, commercialformulation.

Further trials were run at normal application rates of herbicide withnormally added surfactants. The results are shown in Table 8 below.

TABLE 8 Formulation Rate per acre Weed Species, Location, PercentControl concentration (pounds Amaranthus Amaranthus Hibiscus Chenopodium(pounds active Formulation active retroflexus rudis trionium albumTreatment ingredient/gallon) Type ingredient) Geneva, MN Topramezone2.8  SC 0.016 + 57 63 70 80 Commercial surfactant* Topramezone 1.29 DC0.016 + 87 87 88 88 Experimental ‘A’ surfactant* Topramezone 1.29 DC0.016 + 85 85 92 92 Experimental ‘C’ surfactant* *surfactant = 1%methylated sunflower oil + 2.5% urea ammonium nitrate (28%).

Table 8 shows further trials of a commercially used rate of topramezoneapplication with additional surfactants with similar results. Theexperimental formulations of topramezone indicate significant andconsistent advantage over the current commercial formulation oftentaking ‘good’ weed control to an ‘excellent’ category.

The increased activity of the experimental formulations ‘A’ and ‘C’ inthe presence of additional surfactants/UAN (Table 7 and 8) wereparticularly unexpected because it was anticipated these conditionswould mask the differences between formulations. Further, differencesfrom 80 percent control to 90 percent control and 92 to 98 and 100percent control (Table 7) allow this product performance to go from‘good’ to ‘excellent.’ In the case of Setaria (Table 7) effectivecontrol is improved from 53% to 83-92%, i.e., from ‘poor’ to ‘good’control. Table 8 shows the improvement of topramezone activity from 57%control on Amaranthus retroflexus to 85-87% control, from 63% control onAmaranthus rudis to 85-87%, from 70% on Hibiscus to 88-92% and from 80%on Chenopodium to 88-92%.

What is claimed:
 1. A method of treating weeds comprising applying tothe weeds an herbicidally effective amount of a formulation comprising:an agrochemical dispersible concentrate and water, the dispersibleconcentrate comprising: about 10% to about 20% by weight of theconcentrate of topramezone; and about 0.6% to about 90% by weight of theconcentrate of N-methyl pyrrolidone; wherein topramezone is the onlyactive ingredient of the dispersible concentrate; wherein in a ratio ofdispersible concentrate to water is in a range from about 1:50 to1:25,000 by volume, and wherein the formulation is in the form of acolloidal suspension.
 2. The method of claim 1, wherein the weeds aremonocots or dicots.
 3. The method of claim 1, wherein the weeds areresistant to glyphosate, acetolactate synthase inhibitors,protoporphorin oxidase IX inhibitors, or triazine inhibitors.
 4. Themethod of claim 1, wherein the formulation further comprises an additiveselected from the group consisting of a surfactant, urea-ammoniumnitrate (UAN), and combinations thereof.